| Author | Signey-Bildan, Ma. Lolita N. |
| Call Number | AIT Thesis no.EV-92-31 |
| Subject(s) | Sewage--Purification--Activated sludge process
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | Batch experiments were conducted to optimize the conditions of t hermal.
alkali. and thermochemical pretreatments of waste activated sludge from the
standpoints of improved particulate solubilization and increased methane
production. These three types of pretreatment methods were then compared
u sing the same criteria of increased solubilization a nd methane production in
anaerobic digestion.
Alkali. thermal. and thermochemical pretreatments improved the solubilization
of waste activated sludge and en hanced the methane production in the subsequent
digestion. Alkali pretreatment at 0.3 gNaOH/gVSS dose for 30 min contact time
solubilized 9% of raw sludge VSS. and increased the methane conversion rate at
8 clays HRT by 30% over the unpretreatecl WAS (control). On the other hand,
thermal pretreatment at 11 5°C temperature for 15 min contact time solubilized 18%
of raw sludge VSS. In crease in methane conversion rate over the control at 8
days HRT was 1603.
Thermochemical pretreatment at J 15°C temperature. 0.3 gNaOH/gVSS dose for
5 min contact bme solubilized more raw slu dge VSS (36% solubilization rate) than
that attained from either alkali or thermal pretreatment. Digestion at 8 days HRT
increased. the methane conversion rate by only 1153 over t h e control. a value
lower than that obtained from thermal pretreatment. However, digestion
performance of the the1·mochemically pretreated slu dge improved at low
F(COD)/M(VSS) loading. and at 0.25 gCOD/gVSSseed. methane conversion rate at
8 days HRT was increased by as much as 220% over the control. an improvement
of 74% and 20% over alkali pretreatment and heat pretreatment, respectively. |
| Year | 1992 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. EV-92-31 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Environmental Engineering and Management (EV) |
| Chairperson(s) | Tanaka, Shuzo |
| Examination Committee(s) | Chongrak Polprasert;Fujii, Shigeo |
| Scholarship Donor(s) | The Gove rnment of New Zealand |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1992 |